This invention relates to an improvement of U.S. Pat. No. 4,675,478 issued June 23, 1987 on an invention by the present applicant, more particularly to an electric power control switch device which is available for controlling a power supply to an electric heater with one heater.
The U.S. Pat. No. 4,675,478 by the present applicant discloses a switch device with timing cam being mounted on a rotary output shaft of a reducer driven by a motor; a first switch means for the power supply to the motor is installed on the upper portion of a housing and having a plurality of limbs, with contact or contacts adapted to be able to contact to one another at their ends, extended from each other; a pair of second switch means for engaging the limbs to detach the contats from one another and for disengaging from the limbs to attach the contacts to one another, with a pair of bars transversely extended from each second switch means having electrical and mechanical contacts thereon; and a timing cam for engaging the mechanical contacts to detach the electrical contacts of the transverse bar from each other and for disengaging from the mechanical contacts to attach the electrical contacts to each other, in order to make a periodical power appliance to each heater.
The switch device disclosed in above U.S. Pat. No. 4,675,478 is preferable to employ on electric heaters with two heaters. In the case of being employed on electric heaters with only one heater, it is undesirable to adapt the above U.S. Pat. No. 4,675,478 requiring great bulk for installation.